Financial Assets and Liabilities Accounted for at Fair Value on Nonrecurring Basis (Detail) (Fair Value, Measurements, Nonrecurring, USD $)	Sep. 30, 2012
ASSETS
Oil and gas properties, net	$ 19,919
LIABILITIES
Asset retirement obligation	57,532
Level 3
ASSETS
Oil and gas properties, net	19,919
LIABILITIES
Asset retirement obligation	$ 57,532

Tangible assets that are held by an entity for use in the production or supply of goods and services, for rental to others, or for administrative purposes and that are expected to provide economic benefit for more than one year; net of accumulated depreciation. Examples include land, buildings, machinery and equipment, and other types of furniture and equipment including, but not limited to, office equipment, furniture and fixtures, and computer equipment and software, net of accumulated depreciation.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 157

-Paragraph 33

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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